Site Mobile Navigation

Is ‘Do Unto Others’ Written Into Our Genes?

Many people will say it is morally acceptable to pull a switch that diverts a train, killing just one person instead of the five on the other track. But if asked to save the same five lives by throwing a person in the trains path, people will say the action is wrong. This may be evidence for an ancient subconscious morality that deters causing direct physical harm to someone else. An equally strong moral sanction has not yet evolved for harming someone indirectly.Credit
Yarek Waszul

Where do moral rules come from? From reason, some philosophers say. From God, say believers. Seldom considered is a source now being advocated by some biologists, that of evolution.

At first glance, natural selection and the survival of the fittest may seem to reward only the most selfish values. But for animals that live in groups, selfishness must be strictly curbed or there will be no advantage to social living. Could the behaviors evolved by social animals to make societies work be the foundation from which human morality evolved?

In a series of recent articles and a book, “The Happiness Hypothesis,” Jonathan Haidt, a moral psychologist at the University of Virginia, has been constructing a broad evolutionary view of morality that traces its connections both to religion and to politics.

Dr. Haidt (pronounced height) began his research career by probing the emotion of disgust. Testing people’s reactions to situations like that of a hungry family that cooked and ate its pet dog after it had become roadkill, he explored the phenomenon of moral dumbfounding — when people feel strongly that something is wrong but cannot explain why.

Dumbfounding led him to view morality as driven by two separate mental systems, one ancient and one modern, though the mind is scarcely aware of the difference. The ancient system, which he calls moral intuition, is based on the emotion-laden moral behaviors that evolved before the development of language. The modern system — he calls it moral judgment — came after language, when people became able to articulate why something was right or wrong.

The emotional responses of moral intuition occur instantaneously — they are primitive gut reactions that evolved to generate split-second decisions and enhance survival in a dangerous world. Moral judgment, on the other hand, comes later, as the conscious mind develops a plausible rationalization for the decision already arrived at through moral intuition.

Moral dumbfounding, in Dr. Haidt’s view, occurs when moral judgment fails to come up with a convincing explanation for what moral intuition has decided.

So why has evolution equipped the brain with two moral systems when just one might seem plenty?

“We have a complex animal mind that only recently evolved language and language-based reasoning,” Dr. Haidt said. “No way was control of the organism going to be handed over to this novel faculty.”

He likens the mind’s subterranean moral machinery to an elephant, and conscious moral reasoning to a small rider on the elephant’s back. Psychologists and philosophers have long taken a far too narrow view of morality, he believes, because they have focused on the rider and largely ignored the elephant.

Dr. Haidt developed a better sense of the elephant after visiting India at the suggestion of an anthropologist, Richard Shweder. In Bhubaneswar, in the Indian state of Orissa, Dr. Haidt saw that people recognized a much wider moral domain than the issues of harm and justice that are central to Western morality. Indians were concerned with integrating the community through rituals and committed to concepts of religious purity as a way to restrain behavior.

On his return from India, Dr. Haidt combed the literature of anthropology and psychology for ideas about morality throughout the world. He identified five components of morality that were common to most cultures. Some concerned the protection of individuals, others the ties that bind a group together.

Of the moral systems that protect individuals, one is concerned with preventing harm to the person and the other with reciprocity and fairness. Less familiar are the three systems that promote behaviors developed for strengthening the group. These are loyalty to the in-group, respect for authority and hierarchy, and a sense of purity or sanctity.

The five moral systems, in Dr. Haidt’s view, are innate psychological mechanisms that predispose children to absorb certain virtues. Because these virtues are learned, morality may vary widely from culture to culture, while maintaining its central role of restraining selfishness. In Western societies, the focus is on protecting individuals by insisting that everyone be treated fairly. Creativity is high, but society is less orderly. In many other societies, selfishness is suppressed “through practices, rituals and stories that help a person play a cooperative role in a larger social entity,” Dr. Haidt said.

He is aware that many people — including “the politically homogeneous discipline of psychology” — equate morality with justice, rights and the welfare of the individual, and dismiss everything else as mere social convention. But many societies around the world do in fact behave as if loyalty, respect for authority and sanctity are moral concepts, Dr. Haidt notes, and this justifies taking a wider view of the moral domain.

The idea that morality and sacredness are intertwined, he said, may now be out of fashion but has a venerable pedigree, tracing back to Emile Durkheim, a founder of sociology.

Dr. Haidt believes that religion has played an important role in human evolution by strengthening and extending the cohesion provided by the moral systems. “If we didn’t have religious minds we would not have stepped through the transition to groupishness,” he said. “We’d still be just small bands roving around.”

Religious behavior may be the result of natural selection, in his view, shaped at a time when early human groups were competing with one another. “Those who found ways to bind themselves together were more successful,” he said.

Dr. Haidt came to recognize the importance of religion by a roundabout route. “I first found divinity in disgust,” he writes in his book “The Happiness Hypothesis.”

The emotion of disgust probably evolved when people became meat eaters and had to learn which foods might be contaminated with bacteria, a problem not presented by plant foods. Disgust was then extended to many other categories, he argues, to people who were unclean, to unacceptable sexual practices and to a wide class of bodily functions and behaviors that were seen as separating humans from animals.

“Imagine visiting a town,” Dr. Haidt writes, “where people wear no clothes, never bathe, have sex ‘doggie style’ in public, and eat raw meat by biting off pieces directly from the carcass.”

An error has occurred. Please try again later.

You are already subscribed to this email.

He sees the disgust evoked by such a scene as allied to notions of physical and religious purity. Purity is, in his view, a moral system that promotes the goals of controlling selfish desires and acting in a religiously approved way.

Notions of disgust and purity are widespread outside Western cultures. “Educated liberals are the only group to say, ‘I find that disgusting but that doesn’t make it wrong,’ ” Dr. Haidt said.

Working with a graduate student, Jesse Graham, Dr. Haidt has detected a striking political dimension to morality. He and Mr. Graham asked people to identify their position on a liberal-conservative spectrum and then complete a questionnaire that assessed the importance attached to each of the five moral systems. (The test, called the moral foundations questionnaire, can be taken online, at www.YourMorals.org.)

They found that people who identified themselves as liberals attached great weight to the two moral systems protective of individuals — those of not harming others and of doing as you would be done by. But liberals assigned much less importance to the three moral systems that protect the group, those of loyalty, respect for authority and purity.

Conservatives placed value on all five moral systems but they assigned less weight than liberals to the moralities protective of individuals.

Dr. Haidt believes that many political disagreements between liberals and conservatives may reflect the different emphasis each places on the five moral categories.

Take attitudes to contemporary art and music. Conservatives fear that subversive art will undermine authority, violate the in-group’s traditions and offend canons of purity and sanctity. Liberals, on the other hand, see contemporary art as protecting equality by assailing the establishment, especially if the art is by oppressed groups.

Extreme liberals, Dr. Haidt argues, attach almost no importance to the moral systems that protect the group. Because conservatives do give some weight to individual protections, they often have a better understanding of liberal views than liberals do of conservative attitudes, in his view.

Dr. Haidt, who describes himself as a moderate liberal, says that societies need people with both types of personality. “A liberal morality will encourage much greater creativity but will weaken social structure and deplete social capital,” he said. “I am really glad we have New York and San Francisco — most of our creativity comes out of cities like these. But a nation that was just New York and San Francisco could not survive very long. Conservatives give more to charity and tend to be more supportive of essential institutions like the military and law enforcement.”

Steven Pinker, a cognitive scientist at Harvard, said, “I’m a big fan of Haidt’s work.” He added that the idea of including purity in the moral domain could make psychological sense even if purity had no place in moral reasoning.

But Frans B. M. de Waal, a primatologist at Emory University, said he disagreed with Dr. Haidt’s view that the task of morality is to suppress selfishness. Many animals show empathy and altruistic tendencies but do not have moral systems.

“For me, the moral system is one that resolves the tension between individual and group interests in a way that seems best for the most members of the group, hence promotes a give and take,” Dr. de Waal said.

He said that he also disagreed with Dr. Haidt’s alignment of liberals with individual rights and conservatives with social cohesiveness.

“It is obvious that liberals emphasize the common good — safety laws for coal mines, health care for all, support for the poor — that are not nearly as well recognized by conservatives,” Dr. de Waal said.

That alignment also bothers John T. Jost, a political psychologist at New York University. Dr. Jost said he admired Dr. Haidt as a “very interesting and creative social psychologist” and found his work useful in drawing attention to the strong moral element in political beliefs.

But the fact that liberals and conservatives agree on the first two of Dr. Haidt’s principles — do no harm and do unto others as you would have them do unto you — means that those are good candidates to be moral virtues. The fact that liberals and conservatives disagree on the other three principles “suggests to me that they are not general moral virtues but specific ideological commitments or values,” Dr. Jost said.

In defense of his views, Dr. Haidt said that moral claims could be valid even if not universally acknowledged.

“It is at least possible,” he said, “that conservatives and traditional societies have some moral or sociological insights that secular liberals do not understand.”

A version of this article appears in print on , on Page F1 of the New York edition with the headline: Is ‘Do Unto Others’ Written Into Our Genes?. Order Reprints|Today's Paper|Subscribe